1. Field of the Invention
The invention relates to a test module for comparative testing of an electronic component, a simulation module that simulates the functions of the electronic component, and a method for comparative testing of such an electronic component and of such a simulation module.
2. Description of Related Art
The design of electronic components is often computer-assisted. In this context, an entire circuit is designed and tested on the computer. The computer simulation module designed in the process simulates the functions of the real electronic component essentially in the form of a program. In addition, the simulation module can use input and output interfaces to interact with one or more external modules which are also provided for interplay with the real electronic component. In this context, appropriate signals (in particular, digital signals) are interchanged between the simulation module and an external module.
Only after the electronically designed circuit has responded satisfactorily is the real electronic component produced in the form of an electronic circuit. The electronic circuit and its interplay with the external module is then tested. In this context, discrepancies may arise in the interplay between the external module and the real electronic component and between the external module and the simulation module. These discrepancies can be caused, for example, by discrepancies between the real structural elements of the electronic component and the simplified computer models in the simulation module. The discrepancies may also be attributable to faults in the electronic component. For these reasons, the timing response and the signal contents of the interplay between the external module and the electronic component and between the external module and the simulation module are checked. Logs are produced and manually controlled both for the connection between the external module and the electronic component and for the connection between the external module and the simulation module. This procedure is complex, however, and may additionally result in discrepancies remaining undiscovered.
It is therefore an object of the invention to specify a test module that can be used to achieve simplified comparative testing of the electronic component and of the simulation module. Another object of the invention is to specify an automated method for comparative testing of the electronic component and of the associated simulation model.
The purpose and advantages of the invention will be set forth in, and apparent from, the description and drawings that follow, as well as will be learned through practice of the invention. Additional advantages of the invention will be realized and attained by the elements of the apparatus and methods of using the invention described herein.
The invention relates to a test module for comparative testing of an electronic component provided with at least one input and output interface, and of a simulation module that simulates the functions of the electronic component essentially in the form of a program and likewise has at least one input and output interface. The invention also relates to a method for comparative testing of such an electronic component and of such a simulation module.
In accordance with one aspect of the present invention, a test module for comparative testing of an electronic component is provided with at least one input and output interface. Further, a simulation module is provided that simulates the functions of the electronic components essentially in the form of a program and likewise has at least one input and output interface. The test module has an input/output interface to an external module interacting with the electronic component to be tested and also to the electronic component and the simulation module. Equivalent input interfaces of the electronic component and of the simulation module are connected to one another by the test module. Also, the test module has a comparator for comparing output signals from the electronic component and from the simulation module and has a memory log connected to the comparator.
The test module supplies both the electronic component and the simulation module with the same signals, transmitted from the external module, for example via a bus. Both the electronic component and the simulation module then generate the appropriate response signals, which are supplied to a comparator and are automatically compared. The comparator is connected to a memory log that stores the results of this comparison. In one preferred alternate embodiment of the invention, only those results are stored for which the comparator has detected a difference between the output signals from the electronic components and the output signals from the simulation module. In this embodiment, the memory log stores a fault log which is relatively simple to evaluate.
In the preferred embodiment, the electronic component is a digital electronic circuit which receives digital input signals and generates digital output signals. One specific use of the invention is for the testing of electronic components for motor vehicles, for example, audio and navigation systems components that communicate via a bus customary in motor vehicle applications.
In a preferred alternate embodiment, the test module contains a selection switch that permits output signals from the electronic component and/or from the simulation module to be forwarded to the external module. This allows different scenarios to be produced and tested. By way of example, a first position of the selection switch connects the output signal from the electronic component directly to the external module while the simulation module runs concurrently for control purposes. The differences in the output signals from the electronic component and from the simulation module are recorded in the memory log.
In a second position of the selection switch, the output signals from the simulation module are connected directly to the external module, and the electronic component runs concurrently for control purposes. The differences in the output signals from the simulation module and from the electronic component are recorded in the memory log. By contrast with the first variant, in this case, the reactions of the external component are conditioned by the output signal from the simulation module.
In a third position of the selection switch, both the electronic component and the simulation module are connected to the external module, but the output signals from the simulation module are forwarded to the external module only if the response messages from functions in the electronic component are not correctly implemented.
Thus, in accordance with the present invention, the comparative testing of an electronic component provided with at least one input and output interface and of a simulation module which simulates the functions of the electronic component essentially in the form of a program and likewise has at least one input and output interface, equivalent input interfaces of the electronic component and of the simulation module are connected to one another for receiving signals from an external module interacting with the electronic component to be tested. Output signals from the electronic component and from the simulation module are automatically compared with one another and are stored in a memory log if there are discrepancies.